The term "subject" was conceptualized in different fashions is two usually related theoretical fields: critical theory and psychoanalysis. The constructionist approach, affiliated with thinkers such as Michel Foucault, Louis Althusser, Jacques Derrida and Judith Butler, holds that the subject is the product of cultural and social discourse fields, and in being so the subject is the result of ideology and power struggles which shape and operate him. The constructionist approach denies the possibility of a "universal" subject which is independent of historical context, society, culture, politics, economy, gender and so forth. There is no essential core of subjectivity which precedes its relationship with the social world.
On the other hand, psychoanalysis leaned towards a more essentialist perception of the subject, believing that there is a universal and fixed truth to man which exists in his subconscious. Freud, Jung and Lacan all thought that the human psyche has fixed components which precede experience (in linguistics, Noam Chomsky thinks the same). According to psychoanalysis, the truth of the subject is in the subconscious, and is the subconscious which determines how we fill and act.
What both takes on the nature of the subject have in common is a negation of the subject's autonomy, be it from within or from without. Psychoanalysis holds that the subject is not autonomous due to him being subjected to the subconscious. Critical theory holds that the subject is not autonomous since it is conditioned by cultural discourse. Viewing the subject as conditioned and subjected and as lacking autonomy undermines modern juridical discourse which relies on the concept of mens rea – criminal intention – in order to establish responsibility and penalty for a crime committed. This perception supposes autonomy of the subject, which both psychoanalysis and critical theory deny.